SFP transceiver Types

SFP transceivers are of various types and each type comes with different configurations of transmitter and receiver. It is important to choose a proper transceiver to act as an interface between the device and the cable. This choice of transceiver is usually made based on the type of fiber optic cable. Such SFP transceivers which are used to provide the necessary reach to a fiber optic cable are categorized as optical SFP. These SFP modules are of several versions, wherein each version has different values of working wavelength and working distance: typical wavelength of different modules are 850 nm, 1310 nm and 1550 nm with working distances of 550m (SX), 10 km (LX) and 40 km (XD) respectively. There are also other types of SFP like DWDM, CWDM and bi-directional SFP with single fiber having upstream and downstream working wavelengths of 1310 nm and 1490 nm.

Certain SFP transceivers also use copper cables as interface. This will cause a device in the network to send their data over shielded or unshielded twisted pair cable. Usually such copper cable interfaces are used when the information to be transmitted needs to cover only shorter distances where use of copper cable is more economical than optic fiber cables.